📖 AI Glossary — Glossary for Beginners

This glossary explains technical terms related to Artificial Intelligence used in Celestory and its documentation. Definitions are intentionally simplified to be accessible to everyone.

A

API (Application Programming Interface)

Communication channel between two software programs. When Celestory sends your prompt to an AI model and receives a response, it uses an API. You don't need to understand how it works: Celestory handles it for you.

Asset

Graphic, sound, or text resource used in a project: character image, background, interface icon, sound effect… In AI, generating an asset means creating this resource automatically from a description.

Audio Avatar

Video automatically generated from a character (still portrait) whose lips and facial expressions move in sync with an audio file. Allows creating speaking characters without an actor or camera.

C

Competency Prompt (System Prompt / Role)

Basic instructions given to the AI before the conversation, describing its role, constraints, and behavior rules. Example: « You are a sarcastic old wizard sage. You always answer in verse. You never give a direct answer. » The more precise the competency prompt, the more consistent the model will remain.

Context → see Context Window

Conversational Chat

Textual discussion interface (like a messaging app) integrated into Celestory to interact with textual AI models. The history of exchanges is kept so the AI can keep track of the conversation.

D

Diffusion / Diffusion Model

Type of AI architecture used to generate images and videos. The model starts with random noise (like snow on a TV screen) and progressively refines it until a coherent image corresponding to the prompt is obtained. Flux, LTX-2, Veo, Kling are diffusion models.

F

FPS (Frames Per Second)

Number of still images displayed per second in a video. 25 FPS = classic cinema style. 50 FPS = very fluid video. The higher the FPS, the smoother the video appears, but the larger the file size.

Frame

A still image that makes up a video. A 10-second video at 25 FPS is made up of 250 frames. In AI video generation, the "first frame" is the starting image and the "last frame" is the ending image.

H

HTML5

Web programming language (HyperText Markup Language, version 5). Used for creating interactive interfaces in browsers. In Celestory, the HTML5 block allows you to insert a mini-web page or animation directly into your game. With vibe coding, you can ask the AI to write this code for you in plain English.

I

Image Mask

Black and white image overlaid on a photo or illustration to tell the AI which area to modify (black area = to regenerate, white area = to keep). Used for inpainting.

Inpainting

Technique consisting of regenerating only a specific area of an existing image, leaving the rest intact. Example: correcting the background of a portrait without modifying the character in the foreground.

J

JSON (JavaScript Object Notation)

Text-based data structuring format widely used in computing. Looks like: {"key": "value", "number": 42}. In Celestory, the advanced mode of AI generators allows for entering parameters in JSON for full control over the request.

L

LLM (Large Language Model)

Artificial Intelligence program trained on immense amounts of text to understand and generate human language. Examples: GPT-5, Claude, Mistral, Gemini, Llama, Grok. An LLM can write, summarize, translate, code, analyze, and answer questions.

Loop

Animation or sound designed to repeat indefinitely and smoothly, without an audible or visible break between the end and the beginning. A background music loop plays continuously throughout a game scene.

M

Markdown

Simple and lightweight text formatting format, readable both in plain text and graphically rendered. Examples:

• # Title → Title
• **bold** → bold
• *italic* → italic
• - item → • item
• [link](url) → clickable link

Widely used for documentation, notes, and AI chat interfaces. In Celestory, AI text responses are rendered in Markdown.

Model / AI Model

Artificial Intelligence software trained to perform a specific task (generating text, images, videos, audio). Different models have different strengths in terms of quality, speed, and cost.

Motion Control

AI video generation mode where a character's movements are dictated by a reference video. You provide a character image and a video of a real person moving, and the AI animates your character reproducing those movements.

N

Nocode

Approach to developing applications without writing programming code, using visual interfaces (blocks, connectors, forms). Celestory is a nocode platform: you build your game by assembling blocks rather than coding.

Negative Prompt

Instruction given to an AI model to tell it what it must not include in the generation. Ex: « no text, no blur, no deformed hands ». More common in image and video generation than in text generation.

O

Open source

Software whose source code is published freely and modifiable by everyone. In AI, an open-source model (like Meta's Llama or Black Forest Labs' Flux) can be downloaded, modified, and used without depending on a commercial service.

OpenRouter

API service that acts as a « router » to several different AI models (OpenAI, Mistral, Anthropic, Meta, Google…). Celestory uses it for in-game text generation, allowing access to many models through a single interface.

P

Prompt

Instruction or question you send to an AI model to trigger a generation. The quality of the prompt is decisive for the quality of the result: a precise prompt (style, context, constraints) gives a better result than a vague prompt.

Q

Quota

AI credit consumption limit defined by the creator's subscription plan. Displayed in Celestory as X / Y generations per month.

R

Ratio / Aspect Ratio

Proportions between the width and height of an image or video.

• 16:9 → landscape format (television, computer)
• 9:16 → portrait format (mobile, stories)
• 1:1 → square format (social media)
• 4:3 → classic landscape format (older screens)

Reference Image

Existing image that you provide to an AI model to guide its generation. The model draws inspiration from it to respect a style, composition, or character appearance.

S

Seamless

Quality of an animation or sound loop whose transition between the end and the beginning is imperceptible. A seamless loop can run indefinitely without the player hearing or seeing the break.

Seed

Starting random number that determines the result of an AI generation. By using the same seed with the same prompt, exactly the same result is obtained. Useful for reproducing a generation or generating slight variations of the same result.

Sovereign Model

AI model developed by a European company (e.g., Mistral, based in Paris) or in open source (e.g., Meta's Llama, Black Forest Labs' Flux), independent of the large American platforms like OpenAI, Google, or Anthropic. Main advantage: they can be downloaded and used locally on your own servers, without sending your data abroad.

Sprite

In game development, a graphic image representing a character, object, or interface element, usually with a transparent background so it can be overlaid on a scene.

T

Temperature

Parameter that controls the level of creativity (or randomness) of a textual AI model. A low value (close to 0) gives more predictable and factual answers. A high value (close to 1) gives more creative and surprising answers.

Token

Basic unit used by AI models to process text. One token corresponds approximately to ¾ of a word in English. Examples: "hello" = 1 token, "antidisestablishmentarianism" = 3-4 tokens, a 10-word sentence ≈ 13 tokens. Models are billed and limited in the number of tokens processed.

TTS (Text-to-Speech) → see Speech Synthesis

V

Vibe Coding

Approach to creating code assisted by AI: instead of writing code manually, you describe in natural language (English) what you want to create, and the AI generates the corresponding code. In Celestory, vibe coding mainly applies to the HTML5 block: you describe an interface or animation, and the AI produces the ready-to-use HTML/CSS/JS code.

W

WebP

Modern image format developed by Google, lighter than PNG and JPG while maintaining good quality. Supports transparency like PNG. Ideal for web images and game assets where performance is important.

💡 Can't find a term? Find the full documentation at the Celestory documentation or ask your question directly in the Celestory support.

Updated on: 04/03/2026